Phase adjustment device

ABSTRACT

In a phase adjustment device, in particular a valve train phase adjustment device, with a phase adjusting unit comprising a housing part, an input drive and an output drive which is phase-adjustable with respect to input drive and with a control actuator for controlling a base unit extending partially into the housing part, wherein the phase adjusting unit comprises a valve unit actuatable by the control actuator and having a valve housing in the form of a mounting screw by means of which the output drive is connected for rotation with a drive shaft, the valve housing is provided at its free end with a contoured recess for receiving a tightening tool, which has a corresponding outer contour for the transmission of tightening torques and also accommodating part of a valve spool.

This is a Continuation-In-Part application of pending internationalpatent application PCT/EP2009/006570 filed Sep. 10, 2009 and claimingthe priority of German patent application 10 2008 051 386.5 filed Oct.11, 2008.

BACKGROUND OF THE INVENTION

The invention relates to a phase adjustment device, in particular avalve drive train phase adjustment device for adjusting the valveopening timing of an internal combustion engine with respect to theengine drive shaft.

A valve train phase adjustment device, with a phase adjusting unitcomprising a housing part, a drive means and an output means which isphase-adjustable with respect to the drive means and with a controlactuator connecting unit which is provided for disposing a base unit ofa control actuator unit at least partially in the housing part, whereinthe phase adjusting unit comprises a valve unit which is designed to becontrolled by means of the control actuator unit and which comprises avalve housing in the form of a mounting screw by means of which theoutput means of the phase adjusting unit is non-rotatably connected to adrive shaft, is known from DE 198 17 319 A1.

It is the object of the present invention to provide a phase adjustmentdevice of a particularly compact design.

SUMMARY OF THE INVENTION

In a phase adjustment device, in particular a valve train phaseadjustment device, with a phase adjusting unit comprising a housingpart, an input drive and an output drive which is phase-adjustable withrespect to input drive and with a control actuator for controlling abase unit extending partially into the housing part, wherein the phaseadjusting unit comprises a valve unit actuatable by the control actuatorand having a valve housing in the form of a mounting screw by means ofwhich the output drive is connected for rotation with a drive shaft, thevalve housing is provided at its free end with a contoured recess forreceiving a tightening tool, which has a corresponding outer contour forthe transmission of tightening torques and also accommodating part of avalve spool.

With the design according to the invention, an arrangement is providedfor the valve spool which is particularly advantageous in terms of spacerequirements. The space required between the phase adjusting unit andthe control actuator unit can be reduced, so that the phase adjustmentdevice is of a particularly compact design. The contoured recess ispreferably designed as a TORX. The term “control actuator unit” shouldin this context in particular be understood to describe an actuator unitfor the control of the phase adjusting unit. The term “actuator unit”refers to a unit by means of which a control variable, for example anadjustment distance, can be controlled in dependence on a control signalof a control unit. The term “base unit” should in particular beunderstood to describe a unit comprising parts of the control actuatorunit which can be arranged to be stationary, in particular a unit with acontrol actuator housing and/or with a control actuator stator. Thestationary base unit is preferably provided to drive a movable part ofthe control actuator unit, such as a control actuator armature or anactuating pin.

It is further proposed that the housing part is non-rotatably connectedto the drive means and/or to the output means. In this way, the housingpart can simply be attached to the phase adjusting unit.

It is further proposed that the housing part has a recess which isprovided for the accommodation of a base unit of the control actuatorunit. In this way, the base unit can simply be disposed within thehousing part.

The valve unit advantageously comprises a valve spool controlled bymeans of the adjustment actuator unit.

It is further proposed that the phase adjustment device has a cover unitwhich is designed to close the phase adjusting unit and which has atleast one opening provided for the accommodation of the valve operatingunit. In this way, a location for the phase adjusting unit, inparticular for the valve operating unit of the phase adjusting device,can be provided by particularly simple means.

It is advantageous if the valve unit comprises a central valve which atleast partially connects the output means to a drive shaft. In this way,additional fastening means, such as a mounting screw, can be omitted,resulting in a mounting of the drive shaft which allows a compact designof the phase adjustment device.

The phase adjustment device further may comprise a control actuatorhousing which is at least partially accommodated in the housing part inan assembled state. In this way, an axial space requirement of the phaseadjustment device can be reduced. The control actuator housing isadvantageously arranged to be stationary and assigned to the base unitof the control actuator unit.

The phase adjustment device may furthermore comprise an electromagneticcontrol actuator which is at least partially accommodated in the housingpart in an assembled state providing for a compact structure.

The phase adjustment device further may comprise a control actuatorhousing which is at least partially accommodated in the housing part inan assembled state. In this way, an axial space requirement of the phaseadjustment device can be reduced in an advantageous manner. In thiscontext, it is in particular proposed that the control actuator statoris assigned to the base unit of the control actuator unit.

The phase adjustment device further advantageously comprises anelectromagnetic control actuator which is at least partiallyaccommodated in the housing part in an assembled state. This results ina particularly compact structure.

In a further development of the invention, the housing part is at leastpartially provided for an additional phase adjusting unit. In this way,the additional phase adjusting unit can also be protected in anadvantageous manner. By means of a further phase adjusting unit, it ispossible to provide an additional adjusting force for the adjustment ofthe phase position, which reduces the susceptibility of the phaseadjustment device to faults.

The phase adjustment device advantageously comprises at least onemechanical phase adjusting means which is at least partiallyaccommodated in the housing part. In this way, a particularlyfault-resistant phase adjusting unit can be provided using the phaseadjusting means. The term “mechanical phase adjusting means” describesan adjusting means wherein an adjusting force is provided without resortto a hydraulic, electric and/or magnetic actuator.

The phase adjusting means advantageously comprises a spring means. Inthis way, a particularly simple mechanical phase adjusting means can beimplemented.

The mechanical phase adjusting means is preferably designed toaccommodate at least a part of the base unit. In this way, an availablespace can be used advantageously, so that the axial space requirement inparticular can be kept small.

The phase adjusting unit may include a coupling means which is providedfor coupling the base unit of the control actuator unit rotatably to thephase adjusting unit. In this way, the base unit of the control actuatorunit can be arranged stationarily by particularly simple means,resulting in a particularly simple attachment of the control actuatorunit to a control unit.

The invention will become more readily apparent from the followingdescription of a particular embodiment thereof with reference to theaccompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a cross-sectional view of a phase adjustment device accordingto the invention;

FIG. 2 is a diagrammatic representation of the phase adjustment device;

FIG. 3 is a cross-section al view of a valve unit of the phaseadjustment device: and

FIG. 4 is a perspective view of the valve unit.

DESCRIPTION OF A PARTICULAR EMBODIMENT

FIG. 1 shows a phase adjustment device according to the invention whichis designed as a motor vehicle phase adjustment device for an internalcombustion engine of a motor vehicle. The phase adjustment devicecomprises drive means 12 and output means 13 which are phase-adjustablewith respect to each other. To adjust the phase position, the phaseadjustment device comprises a hydraulic phase adjusting unit 10. Theoutput means 13 can be non-rotatably connected to a drive shaft 22. Thedrive shaft 22 is designed as a camshaft. The drive means 12 is coupledto a crankshaft of the internal combustion engine which is not shown indetail by means of a gear 33.

The phase adjusting unit 10 comprises a vane-type adjuster 34. The phaseadjusting unit 10 further comprises a valve unit 18 by means of whichthe phase adjusting unit 10 is controlled. The vane-type adjuster 34 haspressure chambers 35 of which a part is designed for an adjustment in afirst adjustment direction and a part is designed for an adjustment in asecond adjustment direction. Each of the pressure chambers 35 is boundedby the drive means 12 in one sub-region and by the output means 13 inthe other. In the axial direction, the pressure chambers 35 are boundedby a cover unit 19. The pressure chambers 35 of the vane-type adjuster34 can be connected to an operating fluid source not shown in detail viathe valve unit 18. The phase position is adjusted by the selectiveapplication of an operating fluid pressure to the pressure chambers 35.

The valve unit 18 comprises a central valve 21. The valve unit 18 isnon-rotatably coupled to the output unit 13. A valve housing 36 of thevalve unit 18 is in the form of a mounting screw by means of which theoutput means 13 of the phase adjusting unit 10 is non-rotatablyconnected to the drive shaft 22. In order to transmit a tighteningtorque to the valve housing 36, one end of the valve housing 36 isdesigned as a contoured recess 23 into which a complementary tighteningtool can be inserted. The contoured recess 23 is represented by a TORX.A valve spool 24 for the control of the valve unit 18 is partiallyaccommodated within the contoured recess 23. The valve spool 24 isaxially movable and, in dependence on a switching position, connectsoperating fluid channels to one another by means of which the pressurechambers 35 are connected to the operating fluid source or to oneanother.

The cover unit 19 is disc-shaped and has a central opening 20. Thecentral valve 21 of the valve unit 18 is partially accommodated in theopening 20. In sub-regions, the central valve 21 and the opening 20 haveidentical diameters. By means of the opening 20, a bearing unit isformed whereby the valve unit 18 is supported in the cover unit 19. Thebearing unit is represented by a plain bearing arrangement.

To actuate the valve unit 18, the phase adjustment device comprises acontrol actuator unit 16. The control actuator unit 16 is disposed on aside of the valve unit 18 which is remote from the drive shaft 22. Bymeans of the control actuator unit 16, the valve spool 24 can bedisplaced in a first axial direction. To displace the valve spool 24 ina second axial direction, the valve unit 18 comprises a spring means 38which provides a spring force which opposes an actuator force of thecontrol actuator unit 16.

The control actuator unit 16 comprises a stationary base unit 15. Thebase unit 15 comprises a control actuator housing 25 and parts of anelectromagnetic control actuator 26. Parts of the control actuator 26are disposed in the control actuator housing 25. The control actuatorhousing 25 can be arranged to be stationary by means of a connectingstructure 39. The connecting structure 39 is provided for connecting thecontrol actuator housing 25 to the internal combustion engine.

The control actuator 26 comprises a control actuator stator 27 which ispermanently connected to the control actuator housing 25. The controlactuator stator 27 comprises an electric coil for the generation of anelectric field. The control actuator 26 further comprises a controlactuator armature 28 which is disposed within the control actuatorstator 27. The control actuator armature 28 comprises a permanentmagnet. By means of the coil of the control actuator stator 27, theaxially acting actuator force for the actuation of the valve unit 18 canbe generated on the permanent magnets of the control actuator armature28. This axial actuator force which can be generated by means of thecontrol actuator 26 is directed towards the valve unit 18. The controlactuator stator 27 is assigned to the base unit 15.

The control actuator armature 28 is provided for axial displacementonly. A bearing unit by means of which the control actuator armature 28supported in an axially displaceable manner inhibits a rotary movementof the control actuator armature 28. The control actuator armature 28and the valve spool 24 which is non-rotatably connected to the outputmeans 13 of the phase adjusting unit 10 are rotatably coupled to eachother by means of an actuating pin 40 and a coupling means 32. Thecoupling means 32 transmits the actuator force of the control actuator26 to the valve spool 24 of the valve unit 18.

The coupling means 32 is represented by a ball arranged between twosurfaces. The first surface is joined to the valve spool 24. It isdesigned as a flat surface. The second surface is joined to theactuating pin 40 connected to the control actuator unit 16. The secondsurface has a recess in which the ball is accommodated. The depth of therecess is less than the diameter of the ball. A contact surface betweenthe ball and the adjoining surfaces is minimal, whereby a coupling isimplemented for an axial movement combined with a simultaneousuncoupling for a rotary movement.

The control actuator unit 16 is connected to the phase adjusting unit 10by means of a control actuator connecting unit 14. The phase adjustingunit 10 comprises a housing 41 which is non-rotatably connected to thedrive means 12 of the phase adjusting unit 10. The housing 41 is formedby means of a housing part 11 and the cover unit 19. The cover unit 19is non-rotatably connected to the drive means 12. Via the cover unit 19,the housing part 11 is non-rotatably connected to the drive means 12.The housing part 11 is substantially cylindrical and bounds the housing41 in the radial direction. The cover unit 19 completes the housing 41towards the phase adjusting unit 10. Towards the control actuator unit16, the housing 41 is open. The housing 41 protects the valve unit 18 inparticular.

By means of the control actuator connecting unit 14, a part of the baseunit 15 of the control actuator unit 16 can be accommodated in thehousing 41. For this purpose, the housing part 11 has a central recess17 which can accommodate a part of the base unit 15 or in which the partof the base unit 15 is located in the assembled state. In the assembledstate, the housing 11 or the housing 41 and the base unit 15 of thecontrol actuator unit 16 are arranged to overlap axially. In the radialdirection, the housing 11 and the base unit 15 are arranged at adistance from each other.

In the assembled state, the control actuator housing 25 of the base unit15 is partially accommodated in the recess 17 of the housing part 11.The actuating pin 40 of the control actuator unit 16 also projects intothe recess 17 of the housing part 11. The major part of the couplingmeans 32 is located within the recess 17. The control actuator stator 27of the base unit 15 is likewise partially accommodated in the recess 17.In at least one operating state, in which it is extended, the controlactuator armature 28 is accommodated within the recess 17. Across-sectional surface which is oriented perpendicular to an actuatingdirection of the control actuator unit 16 includes the control actuatorhousing 25 and the control actuator armature 28 of the base unit 15, thecoupling means 32 and the housing part 11.

The phase adjustment device further comprises an additional phaseadjusting unit 29 within the housing part 11. The additional phaseadjusting unit 29 comprises a mechanical phase adjusting means 30 whichcan generate a relative torque between the drive means 12 and the outputmeans 13 in order to adjust the phase position between the drive means12 and the output means 13. By means of the phase adjusting means 30, aphase adjustment by the phase adjusting unit 10 is supported in oneadjustment direction.

The phase adjusting means 30 comprises a spring means 31. The springmeans 31 is designed as a spiral spring. The spring means 31 is housedin a radial space between the housing part 11 and the base unit 15. Thebase unit 15, the housing part 11 and the spring means 31 are nestedinto one another.

If the phase position is adjusted in the first adjustment direction bymeans of the hydraulic phase adjusting unit 10, the spring means 31 ofthe additional phase adjusting unit 29 is loaded. The spring means 31produces an adjusting force for an adjustment of the phase position inthe second adjustment direction, which is opposed to the firstadjustment direction.

1. A phase adjustment device of a valve drive train, with a phaseadjusting unit (10) comprising at least a housing part (11), a drivemeans (12) and an output means (13), which is phase-adjustable withrespect to the drive means (12), and with a control actuator connectingunit (14) which is provided for accommodating a base unit (15) of acontrol actuator unit (16) at least partially in the housing part (11),wherein the phase adjusting unit (10) comprises a valve unit (18) with avalve spool (24) which is controlled by the control actuator unit (16)and which comprises a valve housing (36) in the form of a mounting screwfor connecting the output means (13) of the phase adjusting unit (10)non-rotatably to a drive shaft (22), the valve unit (18) having acontoured recess (23) with a rotationally asymmetric contour forengagement by a tightening tool having a corresponding outer contourpermitting the transmission of tightening torques, and the recess (23)also accommodating part of the valve spool (24).
 2. The phase adjustmentdevice according to claim 1, wherein the housing part (11) isnon-rotatably connected to at least one of the drive means (12) and theoutput means (13).
 3. The phase adjustment device according to claim 1,wherein the housing part (11) has a recess (17) which is at leastpartially provided for the accommodation of the base unit (15) of thecontrol actuator unit (16).
 4. The phase adjustment device according toclaim 1, wherein a cover unit (19) which is designed to close the phaseadjusting unit (10) and which has at least one recess (20) provided forthe accommodation of the valve unit (18).
 5. The phase adjustment deviceaccording to claim 1, wherein the valve unit (18) comprises a centralvalve (21) which is at least partially provided in order to connect theoutput means (13) to a drive shaft (22).
 6. The phase adjustment deviceaccording to claim 1, wherein a control actuator housing (25) which isat least partially accommodated in the housing part (11) in an assembledstate.
 7. The phase adjustment device according to claim 1, wherein anelectromagnetic control actuator (26) which is at least partiallyaccommodated in the housing part (11) in an assembled state.
 8. Thephase adjustment device according to claim 1, including at least one ofa control actuator stator (27) and an armature (28) which is at leastpartially accommodated in the housing part (11) in at least one state.9. The phase adjustment device according to claim 1, wherein the housingpart (11) is at least partially provided for an additional phaseadjusting unit (29).
 10. The phase adjustment device according to claim1, including at least one mechanical phase adjusting means (30) which isat least partially accommodated in the housing part (11).
 11. The phaseadjustment device according to claim 10, wherein the phase adjustingmeans (30) comprises a spring means (31).
 12. The phase adjustmentdevice according to claim 10, wherein the mechanical phase adjustingmeans (30) is designed to accommodate at least a part of the base unit(15).
 13. The phase adjustment device according to claim 1, wherein acoupling means (32) which is provided in order to couple the base unit(15) of the control actuator unit (16) rotatably to the phase adjustingunit (10).